Lubricating system for internal combustion engines



May 22, 1934. H. M. NORTHRUP I 1,959,687 v LUBRICATING SYSTEM FOR INTERNAL COMBUSTION ENGINES Filed May 6, 1930 5 Sheets-Sheet l g ZZM W L Q- May 22, 1934- H. M. NORTHRUP LUBRICATING SYSTEM FOR INTERNAL COMBUSTION ENGINES Filed May 6, 1930 3 Sheets-Sheet 2 flijz l 01". 4 3y W M wzsmey y 1934- H. M. NORTHRUP 1,959,687

LUBRICATING SYSTEM FOR INTERNAL COMBUSTION ENGINES Filed May 6, 1930 5 Sheets-Sheet 3 VL Hltorn eys 7 O I Q; 1 0 J 0 j) yam? %vb'jnuenzw' %lbwi @VL Zfi Patented May 22, 1934 UNETE STAT PATENT -EE LUBRICATING SYSTEM FOR INTERNAL COMBUSTION ENGINES Application May 6, 1930, Serial No. 450,181

4 Claims.

This invention relates to lubricating systems for internal combustion engines, and especially, although not exclusively, to lubricating systems of the character shown and described in applica- 5 tion Serial No. 462,775 filed June 21, 1930 by tuart G. Bait-s and assigned to the assignee of the present invention.

A type of lubricating system commonly employed in internal combustion engines for motor vehicles comprises an oil sump or reservoir, an oil tray overlying the reservoir, and a pump for drawing oil from the reservoir and delivering it to the tray, said tray having transverse depressions constituting parallel troughs which correspend in number and arrangement to the engine cylinders and from which the connecting rods may splash up oil, and the arrangement being such as to cause the splashed oil to be fed progressively through the several troughs in succes- 201 sion and finally returned to the reservoir. In

lubricating systems of this or any other type wherein oil drawn from a reservoir is supplied to the working parts of the engine and thereafter returned to the reservoir for recirculation, 5 there is a tendency for the oil returned to the reservoir to flow directly to the inlet of the pump or equivalent circulating means and to be returned to the circulating system without adequate cooling and without sufficient admixture with the main body of oil in the reservoir. This is particularly true in lubricating systems of the character described in the application above referred to, wherein the oil is returned to the reservoir at a point closely adjacent that from which it is drawn.

The present invention has for its object to overcome the above difficulties and to insure the adequate cooling of the oil returned to the reservoir from the circulating system and its thorough admixture with the main body of oil in the reservoir before being again supplied to the engine. To this end, the invention consists in providing the reservoir with means, preferably in the form of a labyrinthine baffle having a portion arranged between the point at which the oil is drawn from the reservoir and. the point where it is returned thereto, for compelling said oil to flow through the reservoir in a circuitous path traversing a very considerable part of the area of the reservoir in passing from the latter point to the former.

The invention will best be understood from the following description of a preferred embodiment thereof illustrated in the accompanying drawings, but it will. also be understood that the par- 55 ticular construction described and shown has been chosen for purposes of exemplification merely, and that the invention, as defined by the claims hereunto appended, may be otherwise embodied without departure from its spirit and 500138.

In said drawings:

Fig. 1 is a diagrammatic longitudinal sectional view of a motor vehicle engine having a lubricating system embodying the invention.

Figs. 2 and 8 are sections taken substantially on the lines 2-2 and 3-3, respectively, Fig. 1.

Fig. 4 is a sectional perspective view of the oil tray.

Fig. 5 is a plan view of the oil reservoir or sump with the tray removed.

In the drawings (see particularly Fig. 1) is shown an internal combustion engine having a cam shaft mounted at its ends in front and rear bearings 16 and 17, a crank shaft 18 journalled at its ends in front and rear bearings 19 and 20 and at intermediate points in bearings 21, said crank shaft having cranks 22 respectively connected with the several pistons 23 by connecting rods 24, an oil tray 25 beneath the crank shaft 18, and an oil reservoir 26 beneath the oil tray 25. The oil tray 25 is formed with transversely extending depressions 2'? which serve as troughs in which the oil collects. The depressions are equal in number to the cranks 22 and are so positioned that fingers or dippers 28 on the ends of the connecting rods 24 will splash up oil from the several troughs. Along one side of the oil tray at the ends of the respective troughs are interceptors 29 which control the volume of the oil splashed up by the revolving cranks and limit s the area of the oil mist which tends to form therearound. Attached to the oil tray behind each of the interceptors 29, with the exception of those corresponding to the troughs 27a and 2% adjacent and at opposite sides of the longitudinal center of the tray, are conveyors or baffles 30 (Figs. 2 and 4) so arranged that oil splashed from each trough will be prevented from returning to that trough and will be fed or caused to flow into the trough lying next adjacent thereto in the direction of said longitudinal center. Adjacent the longitudinal center of the tray and at the same side thereof as the baii'ies 30, said tray is formed with an opening 31 (see Fig. 3) having at its inner edge a baffle 32 (see also Fig. l) over which the oil from the troughs 27a and 27b is splashed as indicated by the arrows on Fig. i, said oil being returned to the reservoir 26 through the opening 31. The oil pump 33 (Fig. l) which may be of any suitable construction and driven by the usual connections with the engine, an inlet communicating with a pipe 34 and two outlets communicating respectively with pipes 35 and 36. The pipe 34 leads from the oil reservoir 25 at approximately the longitudinal center of the r latter, but at a point spaced inwardly of the discharge opening 31, as shown most clearly in Fig. 3, the intake end of said pipe being preferably protected by a suitable oil screen 44. The pipe 35 delivers oil to the timing gearings 37 at the forward end of the engine, whence said oil is discharged into the endmost trough 270 at the front of the engine, a portion of said oil passing through the forward cam shaft and crank shaft bearings 16 and 19. The pipe 36 is arranged to discharge oil upon the rear cam shaft and crank shaft bearings 17 and 20, whence it passes to the endmost trough 27d at the rear end of the engine.

Within the oil reservoir 26 at the bottom thereof is a baffle which is preferably of the labyrinthine form shown and is preferably composed of two sections 39a and 39b. The sections 39a comprises a longitudinally disposed portion 40 interposed between the discharge opening 31 of the oil tray and the intake pipe 34 of the pump, said portion extending for the greater part of the length of the reservoir and terminating in transversely disposed portions 41 which extend the greater part of the width of the tray. At the opposite side of the reservoir from the longitudinally exposed portion 40, the baffle includes a plurality of additional, spaced, parallel, longitudinally disposed portions 42 and 43, the former constituting extensions of the transverse portions 41 of the section 39c and the latter constituting parts of the section 3%. The adjacent ends of the portions 42 are spaced from one another, are turned outwardly and welded or otherwise secured to the adjacent wall of the reservoir, and are formed with openings 45 for the passage of oil. The adjacent ends of the portions 43 are likewise separated by an offset portion 46. The sections 39a and 392) are both formed along the lower edges of their several portions with flanges 47 welded or otherwise secured to the bottom of the reservoir.

The direction of circulation of the oil is indicated by the arrows on the several views of the drawings. It will be seen that the oil drawn from the reservoir 26 by the pump 33 through the pipe 34 is delivered by said pump to the endmost troughs 27c and 27d. Said oil is splashed by the fingers or clippers 28 upon the working parts of the engine, being caused by the bafiies 30 to be fed progressively through the several troughs 27 in succession toward the center of the tray until it reaches the troughs 27a and 27b from which said oil is splashed over the bafiie 32 and passes through the opening 31 to the reservoir 26 at the outer side of the longitudinally disposed portion 40 of the baflie in said reservoir. Said baffie prevents the oil thus returned to the reservoir from passing directly to the intake of the pipe 34 and compels it to flow in a circuitous path, traversing a very considerable portion of the area of the reservoir, before reaching said intake. Thus, as shown most clearly in Fig. 5, the oil stream entering the reservoir through the opening 31 divides into two streams which flow in opposite directions, following the longitudinal portion 40 of the baffle substantially to the ends of the reservoir, thence across the reservoir, following the transverse portions 41, and thence in a circuitous path following the longitudinal portions 42 and 43 to points whence it may pass, through the screen 44, into the intake 34.

It will be seen that this circuitous flow of the oil from the point where it is returned to the res ervoir to the point where it is again drawn therefrom gives said oil ample time to be adequately cooled, provides for the circulation of substantially the complete body of oil in the reservoir, and insures a supply of cool, relatively undiluted oil to the working parts of the engine, thereby fully utilizing all of the lubricating qualities and efiiciency of the oil.

I claim:

1. In an internal combustion engine, a lubricating system including, in combination, an oil reservoir, an oil tray overlying said reservoir and provided with a plurality of troughs, means for drawing oil from said reservoir and delivering it to said tray, means for splashing oil from each of said troughs, means for causing the splashed oil to be fed progressively through said troughs in succession, said tray having an opening through which the oil is returned to said reservoir, and means in said reservoir for compelling said oil to flow in a circuitous path from the point where it is returned to said reservoir to the point where it is drawn therefrom.

2. In an internal combustion engine, a lubricating system including, in combination, an oil reservoir, an oil tray overlying said reservoir and provided with a plurality of troughs, means for drawing oil from substantially the longitudinal center of said reservoir and delivering it to both ends of said tray, means for splashing oil from each of said troughs, means for causing the splashed oil to be fed progressively through said troughs in succession from the ends toward the center of the tray, said tray having an opening adjacent its longitudinal center through which the oil is returned to said reservoir, and means in said reservoir for compelling said oil to flow in a circuitous path from the point where it is returned to said reservoir to the point where it is drawn therefrom.

3. In an internal combustion engine, a lubricating system including, in combination, an oil reservoir, circulating means for drawing oil from one point in the reservoir, supplying it to the working parts of the engine and thereafter returning it to another point in the reservoir, and a baffle extending upward from the bottom of the reservoir between said points, said baflie being arranged to permit a portion of the oil returned to flow in one circuitous path between said points and another portion to flow in a different circuitous path between said points, at least a portion of said paths extending parallel to said bafiie.

4. In an internal combustion engine, a lubricating system including, in combination, an oil reservoir, an oil tray overlying said reservoir, means for drawing oil from substantially the longitudinal center of said reservoir and delivering it to said tray, said tray having an opening adjacent the longitudinal center thereof through which oil is returned to said reservoir, and a baifie in said reservoir comprising a longitudinally disposed portion arranged between the point at which said oil is drawn from said reservoir and the point where it is returned thereto, transversely disposed portions at the ends of said longitudinally disposed portion, and a plurality of additional longitudinal disposed portions for causing the oil, after following said transversely disposed portions, to flow in a circuitous path to said first named point.

HOMER M. NORTHRUP. 

